Method and apparatus for combining webs



P 1968 A. s. BAHRANI A 3,399,884

METHOD OF AND APPARATUS FOR COMBINING WEBS Filed March 15, 1966 2Sheets-Sheet 1 INVENTOR Abdul S. Bohroni BY 47 W- AT RNEYS 2Sheets-Sheet 2 A. S. BAHRANI METHOD OF AND APPARATUS FOR COMBINING WEBSSept. 3, 1968 Filed March 15, 1966 INVENTOR. Abdul S. Bohroni ORNEYS mW///IIIIIIIIIIIIIIIIII United States Patent 3,399,884 METHOD ANDAPPARATUS FOR COMBINING WEBS Abdul S. Bahrani, Colerain Township,Hamilton County, Ohio, assignor to The Procter & Gamble Company,Cincinnati, Ohio, a corporation of Ohio Filed Mar. 15, 1966, Ser. No.534,380 7 Claims. (Cl. 270-52) ABSTRACT OF THE DISCLOSURE Apparatus andmethod for continuously laterally shifting at least one of a pluralityof side-by-side moving webs of stretchable material by passing at leastone of the webs between a pair of spaced cantilevered turning bars whichare positioned obliquely to the web to be shifted. The turning bars arerotated as a unit about the axis of one of the bars to cause the web towrap around a portion of each bar, thereby shifting that web laterallyand in position adjacent to the remaining webs.

This invention relates to a method of and apparatus for web handling andmore particularly to a method of and apparatus for initiating andcontinuously effecting the combination of a plurality of moving,stretchable webs to form a multi-ply structure directly on a papermakingmachine which has a winder associated therewith, without the necessityof winding a parent roll for subsequent slitting and rewinding.

In the course of the manufacture of multi-ply creped paper products inweb or sheet form, the combination of the plies which comprise themulti-ply structure is usually effected on apparatus which is separatefrom the machine on which the creped paper itself is made. Typically, afull width web is removed from a paper machine after being wound into alarge roll, usually referred to as a parent roll, which is thentransferred to a combination slitter and rewinder. A pair of parentrolls is then arranged in tandem and each roll is then unwound andsimultaneously severed longitudinally into a plurality of webs of thedesired width which are thereafter combined to form a series of two-plywebs. It can be seen that in forming the multi-ply web in this manner,considerable time is required to transfer the parent rolls to theslitter-rewinder apparatus, to manually thread the webs through theapparatus, and to actually combine the webs into a multi-ply structure.Furthermore, the additional handling which the creped paper undergoeswhen combined in this manner tends to stretch the paper and remove someof the crepe since the paper is controlled by the application of tensionand the commencement of each separate operation in which the paper webis handled involves the sudden application of tension, tending tostretch the paper.

It is an object of this invention to provide a method of and apparatusfor initiating and continuously effecting the combination of a pluralityof sections of a single, stretchable, moving web without the necessityof manually threading the sections through the apparatus effecting thecombination.

It is another object of this invention to provide a method of andapparatus for the manufacture of a multi-ply web of creped paper from asingle parent web, preferably directly on a papermaking machine whichhas a winder associated therewith, without the need for separaterewinding equipment and without removing the parent web from thepapermaking machine, thereby decreasing the loss in degree of crepewhich would otherwise take place.

Briefly stated, in accordance with one aspect of the present invention,a web combination method is provided which comprises the steps ofslitting a single, moving,

stretchable web into a plurality of juxtaposed, narrower webs each ofwhich has a face and reverse face similarly oriented, passing anoutermost web between a pair of spaced cantilevered bars whose axes areparallel and oblique to the path of travel of the web with the webcontiguous the periphery of at least one of the bars, and rotating thebars as a unit about an axis of rotation coincident with the axis of oneof the bars so that the outer web portion is simultaneously caused towrap around a portion of the periphery of each bar. After being shiftedlaterally, the reverse face of the outermost web is adjacent the face ofthe inner web, thereby forming a multi-ply web wherein the faces of eachply are in the same relative positions that they occupied prior to thecombination.

While the specification concludes with claims particularly pointing outand distinctly claiming the subject matter regarded as forming thepresent invention, it is believed the invention will be betterunderstood from the following description taken in connection with theaccompanying drawings in which:

FIGURE 1 is a fragmentary perspective view of web handling apparatusincluding a pair of parallel bars by means of which the presentinvention may be practiced;

FIGURE 2 is a fragmentary perspective view showing the web passingbetween the pair of parallel bars which have been rotatedcounterclockwise about from the position shown in FIGURE 1;

FIGURE 3 is a fragmentary perspective view showing the web and barsrotated approximately an additional 90 counterclockwise past theposition of FIGURE 2 with the outermost web in superposed relationshipwith an inner web;

FIGURE 4 is an end view of the turning bar supporting and rotatingmeans; and

FIGURE 5 is a fragmentary cross-sectional view of the turning barsupporting and rotating means shown taken along the line 5-5 of FIGURE4.

Referring now to the drawings and particularly to FIG- URE 1, there isshown apparatus which can be located between the dryer of a papermakingmachine and a winder associated therewith or at any point in aconverting operation where a multi-ply web is to be formed fromjuxtaposed webs of ply material. In the embodiment shown in FIGURE 1, aweb-supporting means such as roller 8 is attached to a machine frame orthe like (not shown) and serves to support and guide a parent web 10 ofcreped paper, resinous film, or other stretchable material along itspath of travel. The web 10 is fed continuously from a source which isnot shown. The parent web 10 is pulled along its path of travel by afeeding means such as, for example, winder roll 9, and is severed intotwo narrower, juxtaposed webs 11 and 12 by a slitting means 13 supportedby rigid support member 14. The narrower webs 11 and 12 may be of equalwidth or they may be unequal, depending upon the final web structuredesired.

Support member 14 is rigidly mounted to a machine frame or the like (notshown) with slitting means 13 aligned with the direction of web travel.If it is desired to vary the respective widths of webs 11 and 12 fromtime to time, the mounting of the member 14 on the machine frame can bemade laterally adjustable. Slitting means 13 can be a circular bladewhich cuts the web by squeezing it against a backup roller (not shown)positioned beneath parent web 10 and having an annular groove on itsperiphery corresponding to the cutting edge of slitting means 13. Thistype of device is well known to those skilled in the art and it istherefore not necessary to describe it further herein. When the parentweb 10 is a resinous film, it may be desirable to sever it by means of aheated wire.

A support bracket 15 is bolted or otherwise affixed to a suitablesupport frame (not shown) and is positioned adjacent the outer edge ofweb 12 being oriented so that its face is in a plane substantiallyperpendicular to the plane defined by the moving web and forms an anglewith the edge thereof. Bracket 15 serves to support the turningapparatus described below and can be made of any convenient size andthickness commensurate with its function of supporting the turningapparatus.

Rotatably mounted on bracket 15 is bar holder 16 from which spacedparallel bars 17 and .18 are cantilvered. Bar holder 16 can be arectangular, plate-like member having a length at least equal to thespacing between the axes of bars 17 and 18 and is preferably made fromthe same material as bars 17 and 18 (e.g., steel) so that the latter maybe welded or otherwise rigidly attached thereto. As shown in FIGURE 5,holder 16 is carried on a shaft 19 which passes through and isjournalled in bracket 15 by means of bearing 20 which may be of bronzeor of other bearing metals as is well known to those skilled in the art.Although the holder and shaft are shown as an integral structure, thisis not critical to the present invention and these parts could functionas well if they were made from two separate pieces. As a further variantof the structure, the shaft 19 could be an extension of turning bar 17.

Mounted on shaft 19 by means of key 2.1 are ratchet wheel 22 and handcrank 23, which is used to rotate the shaft 19 and thereby bar holder16. Outward axial movement of the crank 23 on the shaft 19 is preventedby means of cotter pin 25 or the like which is spaced from crank 23 bymeans of washer 24. As shown in FIGURE 4, the teeth of ratchet wheel 22cooperate with pawl 26 to prevent counter rotation of shaft 19 andthereby maintains the shaft 19 and bar holder 16 in the desiredposition.

Rotation of shaft 19 can also be accomplished by using a worm and wormgear arrangement (not shown) having a gear ratio of about 40:1 or more.With this arrangement a worm gear is mounted on shaft 19 in a mannersimilar to the mounting of ratchet wheel 22 and the worm is then mountedat right angles to the axis of shaft 19. Counterrotation of the shaft isnot a problem because a worm gear drive having a gear ratio of at leastabout 40:1 is not reversible since driving the worm gear will not causerotation of the worm. The speed reduction capability of the latterarrangement is suitable for use with electric, pneumatic, or hydraulicmotors which can also be employed to turn the shaft .19.

Bars 17 and 18 are cylindrical members having a highly polished outersurface to minimize the friction between the bars and the moving web andare preferably hollow to reduce the weight thereof and thereby themoment load on bar holder 16 and bearing 20. Further reduction infriction can be accomplished by providing means for supplyinglubricating air between the bars and the Web as shown in U.S. Patent1,630,713, granted May 31, 1957, to I. E. Meyer, or as disclosed inapplicants co-pending application Ser. No. 508,922, filed Nov. 22, 1965,now Patent No. 3,366,298. The mounting of turning bars 17 and 18 to barholder 16 can be by means of a welded connection as shown in FIGURE 5,in which case the bars would not rotate with respect to bar holder 16,or they may be rotatably mounted thereto, as on bearings (not shown), topermit rotation of the bars with respect to bar holder .16. The bars aremounted perpendicularly to bar holder 16 and are therefore also obliquethe web direction. A material from which bars 17 and 18 can be made andone which has been found satisfactory for use with creped paper webs is#304 stainless steel which has been polished to give an average surfaceroughness of about 8 microinches. Fiberglas is also a suitable materialbecause of its relatively high strength and light weight, the lattercharacteristic contributing further to the reduction of the moment loadon bar holder 16 and on bearing 20.

Bars 17 and 18 are of unequal length with bar 18 being the longer of thetwo since it is spaced from and rotated about the axis of bar 17 andmust support web 12 when the latter is adjacent web 11 as shown inFIGURE 3. The bars are disposed obliquely to the path of web travel,forming an acute angle therewith which falls within the range of fromabout 30 to about 60 with 45 being preferred so that the web is turnedthrough The unsupported distal ends of the bars are spaced from theproximal ends thereof in the direction of web travel and are positionedadjacent the outer edge of web 12. Although the actual portion of thelengths of the bars .17 and 18 in contact with the web 12 are equalsince the bars are parallel and the web is of uniform width, the barholder 16 is disposed in a plane at an angle with the edge of web 12 andconsequently there is a difference in the effeciive lengths of the bars,i.e. the distance from the bar holder 16 to the distal end of the webcontacting portions of each. This difference is dependent upon both thespacing between the axes of the bars 17 and 18 and the angle formed bytheir axes and the path of travel of web 12. In any case, unless theposition of the bar holder 16 is adapted to be adjusted by movementthereof in the direction of the bar axes the spacing and angle must besuch as to cause the distal end of bar 18, when rotated from theposition shown in FIGURE 1 to that of FIGURE 3, to move a distancetransverse the direction of movement of the webs which is at least asgreat as the distance which the web 12 has to be shifted. The differencein effective lengths may be expressed mathematically as follows:

AL=D cot 0 where AL is the difference between the effective lengths ofthe bars, D is the distance between the bar axes, and 0 is the angledefined by the bar axes and the path of travel of web 12.

Although the bars are shown to be of equal diameter, this is notessential to the practice of the present invention and it is to beunderstood that each of the bars can be of any convenient diameter.Similarly, the overall lengths of bars may be equal, if so desired, butthe prefered configuration of the device is such that the overall lengthof each bar is equal to its effective length. In any event, whenproperly oriented the bars lie completely across web 12 whereby eachcompletely supports web 12 when the web is shifted laterally. Thepreferred configuration, i.e. with the overall lengths of the bars equalto the effective lengths, results in lower bar weights, which minimizesthe moment load on holder 16 and bearing 20. When equal length bars areemployed, bar 17 will necessarily extend beyond the inner edge of theweb 12 in order to place the distal end of bar 18 in alignment with theinner edge of web 12 at which point bar 18 is in position to clear web11 when the bar is turned about the axis of rotation.

The web combination method of the present invention is shown in variousstages of completion in FIGURES 1, 2 and 3.

In the manufacture of paper or other materials in web form the finishedweb is generally wound around a core which substantially corresponds inwidth to the web width. When a parent web is thereafter severed into twoor more narrower webs and the narrower webs are combined to P form a.multi-ply web according to the method hereinafter described, as thewidth of the wound web diminishes because of the combination of thenarrower webs, the result is that the care then has a web thereon whichvaries in width from a wide, single web to a progressively narrowermulti-ply web. Upon completion of the combination of the narrower webs,the resulting multi-ply web is then continuously transferred to adifferent, narrower core to form a roll having a uniform width. Thiscontinuous web transfer is accomplished by methods and apparatus whichare well-known to those skilled in the art and which will therefore notbe described herein.

The combination of webs according to the present invention comprisessevering a moving, parent web of stretchable material into a pair ofadjacent, narrower webs 11 and 12 by slitting means 13. Narrower webs 11and 12 each have a face and reverse face similarly oriented. It isapparent that parent web 10 may be cut into more than two webs bypositioning additional slitting means 13 at spaced intervals thereacrossto give the desired number and width of individual webs. After being sosevered from parent web 10, outer Web 12 passes between bars 17 and 18which are disposed with their axes respectively overlying and underlyingweb 12 such that the latter is capable of passing therebetween. In thisposition, the outer, unsupported or distal ends of bars 17 and 18 areadjacent the edge of web 12 which abuts web 11 and in order to form aspace for the web 12 to pass between the bars, the plane define-d by theaxes of the bars forms an acute angle with the web 12 so that the barsassume a position as shown generally in FIGURE 1. Bar 17, the axis ofwhich coincides with the axis of rotation, overlies web 12 and iscontiguous thereto so that the portion of web 12 upstream of the bar 17is in the same plane as web 11 prior to the combining operation. If bar17 were to be spaced above web 12, after the combining operation to bedescribed is commenced the upstream portion of the web would be lifted,thereby causing a tear at a point immediately upstream of slitting means13. To overcome this tendency when bar 17 is so spaced, it is necessaryto position either a pair of guide rolls (not shown) or a guide bar (notshown) at a point intermediate slitting means 13 and bar 17 in order toprevent elevation of web 12 at the slitting means. The use of such guiderolls or guide bars is well known to those skilled in the art and willtherefore not be described herein.

Bar holder 16 and bars 17 and 18 are caused to rotate as a unit about anaxis of rotation coincident with the axis of bar 17. As disclosed above,the rotation of bar holder 16 can be accomplished by any convenientmeans such as by the hand crank shown in FIGURES 4 and 5 by an electricmotor (not shown) suitably geared to the shaft to which holder 16 isattached to permit the latter to rotate with respect to support bracket15. FIGURE 2 shows the bars rotated counterclockwise so that their axeslie in a plane substantially perpendicular to web 11. Web 12 has at thispoint been elevated to its maximum height above web 11 at a distance atleast equal to the spacing between the bar axes plus the sum of the barradii and has been shifted toward web 11 a distance such that a minorportion thereof overlies web 11. In FIGURE 3 the bars have been rotatedapproximately 90 beyond the position shown in FIGURE 2 and the web 12,which wraps each turning bar through an arc of about 180", has beenshifted laterally the maximum distance and is adjacent to and completelyoverlies web 11. With the bars in the position shown in FIGURE 3 thereverse face of web 12 is apposed the face of web 11 in a plane parallelthereto and the webs 11 and 12 are in position to be wound together on aroll as a two-ply web. The total angular travel of the bars and holderas shown in FIG- URES 1, 2 and 3 covers about 200 of arc.

When combining stretchable webs in the manner described above, the webwhich is shifted will stretch somewhat in the direction of web tnavelwhen the bars are being turned. This is caused by having the webtraverse a greater linear distance as a result of being shiftedrearwardly an amount corresponding to the sum of the spacing between thebar axes and the bar radii. If the web material is elastic and theelastic limit is not exceeded, the turning of the bars will result in anincrease in web tension. If the elastic limit is exceeded but theultimate limit is not, the turning of the bars can result in a permanentelongation of the web. The rate of increase in tension in the web whichhas not had its elastic limit exceeded and the strain imposed on thepermanently elongated web, or the change of length per unit length, will'be dependent upon both the linear speed of the web and the rotationalspeed of the turning apparatus. While maintaining the speed of either ofthese variables constant, an increase in the speed of the other willresult in a greater rate of increase in tension or a greater strain.These changes, however, only take place when the web shifting operationoccurs. Upon its completion a steady-state condition is reached whereina web which does not have its elastic limit exceeded is under increasedtension while a web which has been permanently elongated continues as itdid prior to the initiation of the turning operation. In the latter caseonly the portion of the web which passed around the turning bars whilethe turning apparatus was rotating has experienced stretching with thedegree of stretch and the length of the web so affected dependent uponthe speed of both the web and the turning apparatus.

It can be seen that although the foregoing description contemplates abar rotation when the web is in contact with both the bars of about 200to achieve a lateral web shift equal to the width of the shifted web,increasing the spacing between the bars or decreasing the acute angledefined by the bar axes and the direction of web travel can result inthe same inward, lateral web shift while rotating the bars through asmaller angle. The maximum horizontal shift of web 12 can be expressedmathematically as follows:

H=2(D+d) cos 0 where H is the maximum distance web 12 is movedhorizontally,

D is the center to center spacing of the turning bars,

d is the bar diameter, and

0 is the angle formed by the bar axes and the path of travel of the web.

In this equation it is assumed that the turning bars have the samediameter. Should the bar diameters be unequal, the term enclosed 'withinparentheses on the right hand side of the equation would become where dand d represent the individual bar diameters.

It can be seen that the maximum lateral web shift for a given set ofbars oriented at a given angle with the path of travel of the web occurswhen the plane defined by the bar axes is parallel to the plane of web12. Thus the equation given above is useful for initially determiningthe sizes and orientation of a pair of turning. bars to effect a givenlateral web shift. An expression which is useful for designing theturning equipment where a two-ply web is to be formed from a pair ofequal width webs relates the width of each of the webs to be combined,the angle formed by the bar axes and the direction of web travel, andthe spacing between the bar axes as follows:

W sec 0 where D is the center to center spacing of the two turning bars,

W is the width of each of the individual webs which are to be combined,and

0 is the angle formed by the bar axes and the path of travel of the web.

an additional cutting means 13 such that web is severed into three webswhich can then be combined into a single web by means of an additionalset of turning bars of the same general configuration as described abovebut disposed on the opposite edge of web 10.

While particular embodiments of the invention have been illustrated anddescribed, it will be obvious to those skilled in the art that variouschanges and modifications can be made without departing from the spiritand scope of the invention and it is intended to cover in the appendedclaims all such changes and modifications that are within the scope ofthis invention.

What is claimed is:

1. Apparatus for initiating and continuously efiecting the combinationof a plurality of juxtaposed, coplanar, moving, stretchable Webs into asingle, multi-ply web by shifting at least one of said webs laterally,said apparatus comprising:

(a) means to feed said web along a path of travel;

(b) means to support said web along said path;

(0) at least one pair of spaced, cantilevered, parallel bars disposedobliquely with respect to the path of web travel and positioned so thatone bar underlies the web to be shifted laterally and the other baroverlies it with the distal ends of said bars spaced in the direction ofweb travel from the proximal ends thereof;

(d) means for supporting said bars in fixed, spaced relationship to oneanother; and

(e) means for rotating said supporting means about an axis coincidentwith the axis of one of said bars, whereby the rotation of said supportmeans causes said web to be shifted laterally.

2. The apparatus of claim 1 wherein the parallel bars are of unequallength.

3. The apparatus of claim 2 wherein the difierence in effective lengthsof said parallel bars is expressed by the following relationship:

D is the distance between the bars axes, and 0 is the angle defined bythe bar axes and the path of travel of the web.

4. The apparatus of claim 1 wherein the spacing between the bar axes isdefined as follows:

:HL M

where D is the center to center spacing of the bars,

W is the width of each of the individual webs which are to be combined,and

5 is the angle formed by the bar axes and the path of travel of the web.

5. A method of forming a multi-ply web from a moving, single,stretchable parent web by means of a pair of spaced, cantilevered,parallel, turning bars obliquely disposed to the path of travel of saidweb, which method comprises:

(a) slitting said single, parent web into a plurality of narrower,juxtaposed Webs each having a face and reverse facing similarlyoriented;

(b) passing an outermost of said narrower webs between said pair ofturning bars with said outermost narrower web contiguous the peripheryof one of said bars; and

(c) rotating said pair of parallel bars as a unit about an axiscoincident with the axis of said one of said bars to cause saidoutermost narrower web to be first turned about a portion of theperiphery of said one of said bars and thence about a portion of theperiphery of the other of said bars, whereby the portion of the saidother bar about which the web passes is adjacent the narrower web whichis nearest the outermost web and the reverse face of said outermost webis apposed the face of said narrower web which is nearest the outermostweb to form a multi-ply web wherein the faces of each ply are in thesame relative position that they occupied prior to the combination.

6. The method of claim 5 wherein said parallel bars rotate through anangle of about 200 while in contact with the web and the outermost webwraps each turning bar through an arc of about 180, whereby saidoutermost web is shifted into a plane parallel to the narrower web whichis nearest said outermost web.

7. The method of claim 5 wherein said narrower, juxtaposed webs are ofequal width.

References Cited UNITED STATES PATENTS 2/1895 Daly. 6/1930 Buchanan 9333

